Thermostatic switch.



C. C. NUCKOLS.

THERMOSTATIC SWITCH.

APPLICATION FILED ocnzs. 1913.

iatnted July 18, 1916.

2 SHEETS-SHEET I.

INVESTOR Claude CNuckals BY lzi d zzi% ATTYf C. C. NUCKOLS.

THERMOSTATIOSWITCH.

APPLICATION FILED OCT. 25. I9I3.

,191,336. Patented July18, 1916.

2 SHEETS-SHEET 2.

ITEfiSSEfi INVENTHR J CZaude (ljviwkols ATTY.

1 details.

UNITED STATES PATENT OFFICE. Y

CLAUDE C. NUCKOLS, OF ALBANY, NEW YORK, ASSIGNOR TO CONSOLIDATED CAR-HEATING COMPANY, OE ALBANY, NEW YORK, A CORPORATION OF WESTVIR- GINIA.

THERMOSTATIC SWITCH.

Specification of Letters Patent.

Patented July 13, 3916.

Application filed October 25, 1913. Serial No. 797,238.

To all whom it may concern:

Be it known that I, CLAUDE C. NUoKoLs, a citizen of the United States,residing at Albany, county of Albany, and State of New York, haveinvented certain new and useful Improvements in Thermostatic Switches,the following being a full, clear, and exact disclosure of ,the one formof my invention which I at present deem preferable.

For a detailed description of the present form of my invention,reference may be had to the following specification and to theaccompanying drawings, forming a part thereof, wherein Figures 1 and 2are sections, showing respectively the open and closed positions of theswitch, Figs. 3 and 4: representing In my construction I employ athermostatic element consisting of a corrugated metallic tube closed atboth ends and filled with a liquid having a low boiling point. Thecorrugated tube forms a sort of bellows and being sealed under-a vacuumthe atmospheric pressure will compress the bellows when the liquidcontained therein is condensed. When the temperature reaches the boilingpoint of the liquid it is converted into a vapor which expands againstthe atmospheric pressure and thereby serves to operate the switchelement which, in my construction, consists simply ofa longitudinallyconfined spring normally bowed on one side or the other of its deadcenter and adapted-to be thrown across its dead center by means of asuitable connection with the bellows aforesaid. I

In the drawing the corrugated metal tube is represented at A and isrigidly supported at the right-hand end on the base or standard of theapparatus. Its left-hand end is free to come and go under the expansionand contraction and is provided with an adjustable stem B adapted, toslide freely through an opening in the post G. On the stem B is secureda disk C having a groove in its periphery which is engaged by the arm Dof an angle lever, the other arm thereof, D, being secured to one end ofa spring S. Attached to the arm D and to the contiguousends of thespring S are lateral arms D which engage spaced apart notches in astandard E The other end of spring S enters a V-shaped notch in thestandard E. The spring S is therefore confined longitudinally betweenthe standards E and E and is somewhat longer'than the direct distancebetween the confining members, so as to cause it to assume a bowed formeither above the dead center line, as shown in Fig. 1 of the drawing, orbelow that line when the spring is turned so as to snap suddenly fromthe position shown in the drawing to a corresponding position below thedead center. It will be manifest that as the stem B is 'moved to theright when the bellows contracts, the disk C will turn the angle leverD, D on its pivot until the arm D passes the dead center position,whereupon the spring will suddenly snap across from its upper to itslower position. In its latter position it will come into contact with aninsulated electric-contact F and thereby close the electric circuit. Onthe other hand, when the stem l3 moves to the left as the bellowsexpands the re'- verse operation will take place and the elec triccircuit will be broken. It will be manifest that the contact F may beplaced above instead of below the spring S so as to close the circuit onthe upward instead of the downward movement of the spring and also thattwo springs S may be employed, one closing the circuit on the upward andthe other on the downward movement of the spring. The groove in theperiphery of the disk will be wide enough to allow such slight degree oflost motion between the arm D and the disk as may be necessary to allowthe full throw of the spring into either one of its two positions. Itwill be observed that the initial flexing of the spring S, which maytake place more or less gradually, will occur near the angle-lever D, Dand will not affect that portion of the spring which is in contact withthe stationary contact point F, the said contact being located at oneside of the center of the bow. The electrical connection will bemaintained until the flexing has progressed far enough to cause thespring to snap over its dead center, thereby breaking its contact withpoint F suddenly and positively.

What I claim as new and desire to secure by Letters Patent is:

1. A thermostatic switch comprising than the direct distance betweensaid abutments, whereby the spring is normally bowed under longitudinalcompression, a stationary contact cooperating with said spring contact,and means engaging and moving one end of said spring to vary thelongitudinal compression thereof to throw it across its dead center.

2. A thermostatic switch comprising a thermostatic element, alongitudinally confined spring pivoted at one end and normally bowedbetween its confining members, an electric contact controlled by saidspring and an operating connection between said element and the springfor rotating the pivoted end of the spring across its dead center.

3. A thermostatic switch comprising spaced apart abutments, a contactspring having its ends engaging said abutments, the spring being of agreater length than the direct distance between said abutments, wherebythe spring is normally bowed under longitudinal compression, astationary contact cooperating with said spring contact, athermostatically operated member movable longitudinally with respect tothe contact spring, and a lost motion connection between one end of thesaid contact spring and the said thermostatic member, for varying thelongitudinal compression of the contact spring to throw it across itsdead center.

4. A thermostatic switch comprising spaced apart abutments, a contactspring having its ends engaging said abutments, the spring being of agreater length than the direct distance between said abutments, wherebythe spring is normally bowed under longitudinal compression, astationary contact cooperating with said spring contact, an angle leverattached to one end of said contact spring, and means engaging saidangle lever and movable longitudinally with respect to the contactspring to vary the longitudinal switch comprising spaced apartabutments, a contact spring having its ends engaging said abutments, thespring being of a greater length than the direct distance between saidabutments, whereby the spring is normally bowed under longitudinalcompression, a stationary contact cooperating with said contact spring,and a thermostatic element consisting of an expansible corrugated metaltube containing a vaporizable liquid and having means for engaging andmoving one end of said contact spring to vary the longitudinalcompression thereof, whereby it may be thrown across its dead center.

6. A thermostatic switch comprising a thermostatic element consisting ofan expansible corrugated metal tube-containing a vaporizable liquid, anangle lever operated by the expansion and contraction of said tube, acontact spring connected at one end to one arm of said lever, confiningmembers for the ends of said contact spring, and an electric contactpositioned to be engaged by said contact spring when moved across itsdead center.

7. A thermostatic switch, comprising a thermostatic element, alongitudinally confined contact spring, normally bowed between itsconfining members, an electric contact located at one side of the centerof the bow, and an operating connection movable longitudinally withrespect to said spring contact for throwing the same across its deadcenter.

In witness whereof I have hereunto set my hand, before two subscribingwitnesses, this 9th day of October, 1913.

CLAUDE C. NUCKOLS. lVitnesses JAMES F. MCELROY, Hnnnnn'r A. CAULKINS.

